The air quality in Delhi is usually around 150-250. (Quite horrible as it is)
This huge spike in AQI is caused by unregulated stubble burning in the neighbouring states. Farmers harvest rice and burn the leftovers so that they can hurry up and plant the next crop.
Yep. This pretty much happens every year. Oct to November.
Pollution is a huge problem in this country. Few take it seriously because for most people, life here is all about earning enough to eat and make it to tomorrow.